[llvm] Adding Matching and Inference Functionality to Propeller (PR #160706)

via llvm-commits llvm-commits at lists.llvm.org
Fri Sep 26 06:54:24 PDT 2025


https://github.com/wdx727 updated https://github.com/llvm/llvm-project/pull/160706

>From b35ef3cdc7242ba123f06dafaad2e6bbaf1b03c9 Mon Sep 17 00:00:00 2001
From: wudexin <wudexin at kuaishou.com>
Date: Wed, 24 Sep 2025 18:42:21 +0800
Subject: [PATCH] Adding Matching and Inference Functionality to Propeller

---
 .../CodeGen/BasicBlockMatchingAndInference.h  |  50 +++++
 .../CodeGen/BasicBlockSectionsProfileReader.h |   9 +
 .../llvm/CodeGen/MachineBlockHashInfo.h       | 106 +++++++++++
 llvm/include/llvm/CodeGen/Passes.h            |   7 +
 llvm/include/llvm/InitializePasses.h          |   2 +
 llvm/include/llvm/Object/ELFTypes.h           |  19 +-
 llvm/include/llvm/ObjectYAML/ELFYAML.h        |   1 +
 .../Transforms/Utils/SampleProfileInference.h |  16 ++
 llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp    |  14 +-
 .../BasicBlockMatchingAndInference.cpp        | 172 ++++++++++++++++++
 llvm/lib/CodeGen/BasicBlockSections.cpp       |  85 ++++++++-
 .../BasicBlockSectionsProfileReader.cpp       |  33 ++++
 llvm/lib/CodeGen/CMakeLists.txt               |   2 +
 llvm/lib/CodeGen/MachineBlockHashInfo.cpp     | 111 +++++++++++
 llvm/lib/CodeGen/TargetPassConfig.cpp         |  17 +-
 llvm/lib/Object/ELF.cpp                       |   3 +-
 llvm/lib/ObjectYAML/ELFEmitter.cpp            |   3 +
 llvm/lib/ObjectYAML/ELFYAML.cpp               |   1 +
 .../basic-block-address-map-with-bb-hash.ll   |  96 ++++++++++
 .../ELF/bb-addr-map-pgo-analysis-map.yaml     |   3 +-
 llvm/unittests/Object/ELFObjectFileTest.cpp   | 120 ++++++++++++
 llvm/unittests/Object/ELFTypesTest.cpp        |   4 +-
 22 files changed, 857 insertions(+), 17 deletions(-)
 create mode 100644 llvm/include/llvm/CodeGen/BasicBlockMatchingAndInference.h
 create mode 100644 llvm/include/llvm/CodeGen/MachineBlockHashInfo.h
 create mode 100644 llvm/lib/CodeGen/BasicBlockMatchingAndInference.cpp
 create mode 100644 llvm/lib/CodeGen/MachineBlockHashInfo.cpp
 create mode 100644 llvm/test/CodeGen/X86/basic-block-address-map-with-bb-hash.ll

diff --git a/llvm/include/llvm/CodeGen/BasicBlockMatchingAndInference.h b/llvm/include/llvm/CodeGen/BasicBlockMatchingAndInference.h
new file mode 100644
index 0000000000000..66209d7685ecc
--- /dev/null
+++ b/llvm/include/llvm/CodeGen/BasicBlockMatchingAndInference.h
@@ -0,0 +1,50 @@
+#ifndef LLVM_CODEGEN_BASIC_BLOCK_AND_INFERENCE_H
+#define LLVM_CODEGEN_BASIC_BLOCK_AND_INFERENCE_H
+
+#include "llvm/CodeGen/BasicBlockSectionsProfileReader.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/Transforms/Utils/SampleProfileInference.h"
+
+namespace llvm {
+
+class BasicBlockMatchingAndInference : public MachineFunctionPass {
+private:
+  using Edge = std::pair<const MachineBasicBlock *, const MachineBasicBlock *>;
+  using BlockWeightMap = DenseMap<const MachineBasicBlock *, uint64_t>;
+  using EdgeWeightMap = DenseMap<Edge, uint64_t>;
+  using BlockEdgeMap = DenseMap<const MachineBasicBlock *,
+                                SmallVector<const MachineBasicBlock *, 8>>;
+
+  struct WeightInfo {
+    // Weight of basic blocks.
+    BlockWeightMap BlockWeights;
+    // Weight of edges.
+    EdgeWeightMap EdgeWeights;
+  };
+
+public:
+  static char ID;
+  BasicBlockMatchingAndInference();
+
+  StringRef getPassName() const override {
+    return "Basic Block Matching and Inference";
+  }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+
+  bool runOnMachineFunction(MachineFunction &F) override;
+
+  std::optional<WeightInfo> getWeightInfo(StringRef FuncName) const;
+
+private:
+  StringMap<WeightInfo> ProgramWeightInfo;
+
+  WeightInfo initWeightInfoByMatching(MachineFunction &MF);
+
+  void generateWeightInfoByInference(MachineFunction &MF,
+                                     WeightInfo &MatchWeight);
+};
+
+} // end namespace llvm
+
+#endif // LLVM_CODEGEN_BASIC_BLOCK_AND_INFERENCE_H
diff --git a/llvm/include/llvm/CodeGen/BasicBlockSectionsProfileReader.h b/llvm/include/llvm/CodeGen/BasicBlockSectionsProfileReader.h
index 82dd5feb31dba..497d751b3b26e 100644
--- a/llvm/include/llvm/CodeGen/BasicBlockSectionsProfileReader.h
+++ b/llvm/include/llvm/CodeGen/BasicBlockSectionsProfileReader.h
@@ -54,6 +54,8 @@ struct FunctionPathAndClusterInfo {
   DenseMap<UniqueBBID, uint64_t> NodeCounts;
   // Edge counts for each edge, stored as a nested map.
   DenseMap<UniqueBBID, DenseMap<UniqueBBID, uint64_t>> EdgeCounts;
+  // Hash for each basic block.
+  DenseMap<unsigned, uint64_t> BBHashes;
 };
 
 class BasicBlockSectionsProfileReader {
@@ -86,6 +88,10 @@ class BasicBlockSectionsProfileReader {
   uint64_t getEdgeCount(StringRef FuncName, const UniqueBBID &SrcBBID,
                         const UniqueBBID &SinkBBID) const;
 
+  // Return the complete function path and cluster info for the given function.
+  std::pair<bool, FunctionPathAndClusterInfo>
+  getFunctionPathAndClusterInfo(StringRef FuncName) const;
+
 private:
   StringRef getAliasName(StringRef FuncName) const {
     auto R = FuncAliasMap.find(FuncName);
@@ -195,6 +201,9 @@ class BasicBlockSectionsProfileReaderWrapperPass : public ImmutablePass {
   uint64_t getEdgeCount(StringRef FuncName, const UniqueBBID &SrcBBID,
                         const UniqueBBID &DestBBID) const;
 
+  std::pair<bool, FunctionPathAndClusterInfo>
+  getFunctionPathAndClusterInfo(StringRef FuncName) const;
+
   // Initializes the FunctionNameToDIFilename map for the current module and
   // then reads the profile for the matching functions.
   bool doInitialization(Module &M) override;
diff --git a/llvm/include/llvm/CodeGen/MachineBlockHashInfo.h b/llvm/include/llvm/CodeGen/MachineBlockHashInfo.h
new file mode 100644
index 0000000000000..5de1b567e0309
--- /dev/null
+++ b/llvm/include/llvm/CodeGen/MachineBlockHashInfo.h
@@ -0,0 +1,106 @@
+#ifndef LLVM_CODEGEN_MACHINEBLOCKHASHINFO_H
+#define LLVM_CODEGEN_MACHINEBLOCKHASHINFO_H
+
+#include "llvm/CodeGen/MachineFunctionPass.h"
+
+namespace llvm {
+
+/// An object wrapping several components of a basic block hash. The combined
+/// (blended) hash is represented and stored as one uint64_t, while individual
+/// components are of smaller size (e.g., uint16_t or uint8_t).
+struct BlendedBlockHash {
+private:
+  static uint64_t combineHashes(uint16_t Hash1, uint16_t Hash2, uint16_t Hash3,
+                                uint16_t Hash4) {
+    uint64_t Hash = 0;
+
+    Hash |= uint64_t(Hash4);
+    Hash <<= 16;
+
+    Hash |= uint64_t(Hash3);
+    Hash <<= 16;
+
+    Hash |= uint64_t(Hash2);
+    Hash <<= 16;
+
+    Hash |= uint64_t(Hash1);
+
+    return Hash;
+  }
+
+  static void parseHashes(uint64_t Hash, uint16_t &Hash1, uint16_t &Hash2,
+                          uint16_t &Hash3, uint16_t &Hash4) {
+    Hash1 = Hash & 0xffff;
+    Hash >>= 16;
+
+    Hash2 = Hash & 0xffff;
+    Hash >>= 16;
+
+    Hash3 = Hash & 0xffff;
+    Hash >>= 16;
+
+    Hash4 = Hash & 0xffff;
+    Hash >>= 16;
+  }
+
+public:
+  explicit BlendedBlockHash() {}
+
+  explicit BlendedBlockHash(uint64_t CombinedHash) {
+    parseHashes(CombinedHash, Offset, OpcodeHash, InstrHash, NeighborHash);
+  }
+
+  /// Combine the blended hash into uint64_t.
+  uint64_t combine() const {
+    return combineHashes(Offset, OpcodeHash, InstrHash, NeighborHash);
+  }
+
+  /// Compute a distance between two given blended hashes. The smaller the
+  /// distance, the more similar two blocks are. For identical basic blocks,
+  /// the distance is zero.
+  uint64_t distance(const BlendedBlockHash &BBH) const {
+    assert(OpcodeHash == BBH.OpcodeHash &&
+           "incorrect blended hash distance computation");
+    uint64_t Dist = 0;
+    // Account for NeighborHash
+    Dist += NeighborHash == BBH.NeighborHash ? 0 : 1;
+    Dist <<= 16;
+    // Account for InstrHash
+    Dist += InstrHash == BBH.InstrHash ? 0 : 1;
+    Dist <<= 16;
+    // Account for Offset
+    Dist += (Offset >= BBH.Offset ? Offset - BBH.Offset : BBH.Offset - Offset);
+    return Dist;
+  }
+
+  /// The offset of the basic block from the function start.
+  uint16_t Offset{0};
+  /// (Loose) Hash of the basic block instructions, excluding operands.
+  uint16_t OpcodeHash{0};
+  /// (Strong) Hash of the basic block instructions, including opcodes and
+  /// operands.
+  uint16_t InstrHash{0};
+  /// Hash of the (loose) basic block together with (loose) hashes of its
+  /// successors and predecessors.
+  uint16_t NeighborHash{0};
+};
+
+class MachineBlockHashInfo : public MachineFunctionPass {
+  DenseMap<unsigned, uint64_t> MBBHashInfo;
+
+public:
+  static char ID;
+  MachineBlockHashInfo();
+
+  StringRef getPassName() const override { return "Basic Block Hash Compute"; }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+
+  bool runOnMachineFunction(MachineFunction &F) override;
+
+  uint64_t getMBBHash(const MachineBasicBlock &MBB);
+};
+
+} // end namespace llvm
+
+#endif // LLVM_CODEGEN_MACHINEBLOCKHASHINFO_H
diff --git a/llvm/include/llvm/CodeGen/Passes.h b/llvm/include/llvm/CodeGen/Passes.h
index f17d550623efc..4bee8bec932ef 100644
--- a/llvm/include/llvm/CodeGen/Passes.h
+++ b/llvm/include/llvm/CodeGen/Passes.h
@@ -69,6 +69,13 @@ LLVM_ABI MachineFunctionPass *createBasicBlockSectionsPass();
 
 LLVM_ABI MachineFunctionPass *createBasicBlockPathCloningPass();
 
+/// createBasicBlockMatchingAndInferencePass - This pass enables matching
+/// and inference when using propeller.
+MachineFunctionPass *createBasicBlockMatchingAndInferencePass();
+
+/// createMachineBlockHashInfoPass - This pass computes basic block hashes.
+MachineFunctionPass *createMachineBlockHashInfoPass();
+
 /// createMachineFunctionSplitterPass - This pass splits machine functions
 /// using profile information.
 LLVM_ABI MachineFunctionPass *createMachineFunctionSplitterPass();
diff --git a/llvm/include/llvm/InitializePasses.h b/llvm/include/llvm/InitializePasses.h
index 88272f053c114..bf3895cc6b16d 100644
--- a/llvm/include/llvm/InitializePasses.h
+++ b/llvm/include/llvm/InitializePasses.h
@@ -55,6 +55,7 @@ LLVM_ABI void initializeAlwaysInlinerLegacyPassPass(PassRegistry &);
 LLVM_ABI void initializeAssignmentTrackingAnalysisPass(PassRegistry &);
 LLVM_ABI void initializeAssumptionCacheTrackerPass(PassRegistry &);
 LLVM_ABI void initializeAtomicExpandLegacyPass(PassRegistry &);
+LLVM_ABI void initializeBasicBlockMatchingAndInferencePass(PassRegistry &);
 LLVM_ABI void initializeBasicBlockPathCloningPass(PassRegistry &);
 LLVM_ABI void
 initializeBasicBlockSectionsProfileReaderWrapperPassPass(PassRegistry &);
@@ -62,6 +63,7 @@ LLVM_ABI void initializeBasicBlockSectionsPass(PassRegistry &);
 LLVM_ABI void initializeBarrierNoopPass(PassRegistry &);
 LLVM_ABI void initializeBasicAAWrapperPassPass(PassRegistry &);
 LLVM_ABI void initializeBlockFrequencyInfoWrapperPassPass(PassRegistry &);
+LLVM_ABI void initializeMachineBlockHashInfoPass(PassRegistry&);
 LLVM_ABI void initializeBranchFolderLegacyPass(PassRegistry &);
 LLVM_ABI void initializeBranchProbabilityInfoWrapperPassPass(PassRegistry &);
 LLVM_ABI void initializeBranchRelaxationLegacyPass(PassRegistry &);
diff --git a/llvm/include/llvm/Object/ELFTypes.h b/llvm/include/llvm/Object/ELFTypes.h
index 5a26e2fc31458..ea88e858c89a7 100644
--- a/llvm/include/llvm/Object/ELFTypes.h
+++ b/llvm/include/llvm/Object/ELFTypes.h
@@ -833,6 +833,7 @@ struct BBAddrMap {
     bool MultiBBRange : 1;
     bool OmitBBEntries : 1;
     bool CallsiteEndOffsets : 1;
+    bool BBHash : 1;
 
     bool hasPGOAnalysis() const { return FuncEntryCount || BBFreq || BrProb; }
 
@@ -845,7 +846,8 @@ struct BBAddrMap {
              (static_cast<uint8_t>(BrProb) << 2) |
              (static_cast<uint8_t>(MultiBBRange) << 3) |
              (static_cast<uint8_t>(OmitBBEntries) << 4) |
-             (static_cast<uint8_t>(CallsiteEndOffsets) << 5);
+             (static_cast<uint8_t>(CallsiteEndOffsets) << 5) |
+             (static_cast<uint8_t>(BBHash) << 6);
     }
 
     // Decodes from minimum bit width representation and validates no
@@ -854,7 +856,8 @@ struct BBAddrMap {
       Features Feat{
           static_cast<bool>(Val & (1 << 0)), static_cast<bool>(Val & (1 << 1)),
           static_cast<bool>(Val & (1 << 2)), static_cast<bool>(Val & (1 << 3)),
-          static_cast<bool>(Val & (1 << 4)), static_cast<bool>(Val & (1 << 5))};
+          static_cast<bool>(Val & (1 << 4)), static_cast<bool>(Val & (1 << 5)),
+          static_cast<bool>(Val & (1 << 6))};
       if (Feat.encode() != Val)
         return createStringError(
             std::error_code(), "invalid encoding for BBAddrMap::Features: 0x%x",
@@ -864,10 +867,10 @@ struct BBAddrMap {
 
     bool operator==(const Features &Other) const {
       return std::tie(FuncEntryCount, BBFreq, BrProb, MultiBBRange,
-                      OmitBBEntries, CallsiteEndOffsets) ==
+                      OmitBBEntries, CallsiteEndOffsets, BBHash) ==
              std::tie(Other.FuncEntryCount, Other.BBFreq, Other.BrProb,
                       Other.MultiBBRange, Other.OmitBBEntries,
-                      Other.CallsiteEndOffsets);
+                      Other.CallsiteEndOffsets, Other.BBHash);
     }
   };
 
@@ -920,17 +923,19 @@ struct BBAddrMap {
                    false}; // Metdata for this basic block.
     // Offsets of end of call instructions, relative to the basic block start.
     SmallVector<uint32_t, 1> CallsiteEndOffsets;
+    uint64_t Hash = 0;     // Hash for this basic block.
 
     BBEntry(uint32_t ID, uint32_t Offset, uint32_t Size, Metadata MD,
-            SmallVector<uint32_t, 1> CallsiteEndOffsets)
+            SmallVector<uint32_t, 1> CallsiteEndOffsets, uint64_t Hash = 0)
         : ID(ID), Offset(Offset), Size(Size), MD(MD),
-          CallsiteEndOffsets(std::move(CallsiteEndOffsets)) {}
+          CallsiteEndOffsets(std::move(CallsiteEndOffsets)), Hash(Hash) {}
 
     UniqueBBID getID() const { return {ID, 0}; }
 
     bool operator==(const BBEntry &Other) const {
       return ID == Other.ID && Offset == Other.Offset && Size == Other.Size &&
-             MD == Other.MD && CallsiteEndOffsets == Other.CallsiteEndOffsets;
+             MD == Other.MD && CallsiteEndOffsets == Other.CallsiteEndOffsets &&
+             Hash == Other.Hash;
     }
 
     bool hasReturn() const { return MD.HasReturn; }
diff --git a/llvm/include/llvm/ObjectYAML/ELFYAML.h b/llvm/include/llvm/ObjectYAML/ELFYAML.h
index c90591d009dcd..a7c7c7c436dc2 100644
--- a/llvm/include/llvm/ObjectYAML/ELFYAML.h
+++ b/llvm/include/llvm/ObjectYAML/ELFYAML.h
@@ -163,6 +163,7 @@ struct BBAddrMapEntry {
     llvm::yaml::Hex64 Size;
     llvm::yaml::Hex64 Metadata;
     std::optional<std::vector<llvm::yaml::Hex64>> CallsiteEndOffsets;
+    std::optional<llvm::yaml::Hex64> Hash;
   };
   uint8_t Version;
   llvm::yaml::Hex8 Feature;
diff --git a/llvm/include/llvm/Transforms/Utils/SampleProfileInference.h b/llvm/include/llvm/Transforms/Utils/SampleProfileInference.h
index 7231e45fe8eb7..2b4db171bfdfb 100644
--- a/llvm/include/llvm/Transforms/Utils/SampleProfileInference.h
+++ b/llvm/include/llvm/Transforms/Utils/SampleProfileInference.h
@@ -130,6 +130,11 @@ template <typename FT> class SampleProfileInference {
   SampleProfileInference(FunctionT &F, BlockEdgeMap &Successors,
                          BlockWeightMap &SampleBlockWeights)
       : F(F), Successors(Successors), SampleBlockWeights(SampleBlockWeights) {}
+  SampleProfileInference(FunctionT &F, BlockEdgeMap &Successors,
+                         BlockWeightMap &SampleBlockWeights,
+                         EdgeWeightMap &SampleEdgeWeights)
+      : F(F), Successors(Successors), SampleBlockWeights(SampleBlockWeights), 
+        SampleEdgeWeights(SampleEdgeWeights) {}
 
   /// Apply the profile inference algorithm for a given function
   void apply(BlockWeightMap &BlockWeights, EdgeWeightMap &EdgeWeights);
@@ -157,6 +162,9 @@ template <typename FT> class SampleProfileInference {
 
   /// Map basic blocks to their sampled weights.
   BlockWeightMap &SampleBlockWeights;
+
+  /// Map edges to their sampled weights.
+  EdgeWeightMap SampleEdgeWeights;
 };
 
 template <typename BT>
@@ -266,6 +274,14 @@ FlowFunction SampleProfileInference<BT>::createFlowFunction(
       FlowJump Jump;
       Jump.Source = BlockIndex[BB];
       Jump.Target = BlockIndex[Succ];
+      auto It = SampleEdgeWeights.find(std::make_pair(BB, Succ));
+      if (It != SampleEdgeWeights.end()) {
+        Jump.HasUnknownWeight = false;
+        Jump.Weight = It->second;
+      } else {
+        Jump.HasUnknownWeight = true;
+        Jump.Weight = 0;
+      }
       Func.Jumps.push_back(Jump);
     }
   }
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 701a6a2f0f7a0..1cfba9dcc3551 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -40,6 +40,7 @@
 #include "llvm/CodeGen/GCMetadataPrinter.h"
 #include "llvm/CodeGen/LazyMachineBlockFrequencyInfo.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineBlockHashInfo.h"
 #include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
 #include "llvm/CodeGen/MachineConstantPool.h"
 #include "llvm/CodeGen/MachineDominators.h"
@@ -182,6 +183,8 @@ static cl::opt<bool> PrintLatency(
     cl::desc("Print instruction latencies as verbose asm comments"), cl::Hidden,
     cl::init(false));
 
+extern cl::opt<bool> EmitBBHash;
+
 STATISTIC(EmittedInsts, "Number of machine instrs printed");
 
 char AsmPrinter::ID = 0;
@@ -461,6 +464,8 @@ void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<GCModuleInfo>();
   AU.addRequired<LazyMachineBlockFrequencyInfoPass>();
   AU.addRequired<MachineBranchProbabilityInfoWrapperPass>();
+  if (EmitBBHash)
+    AU.addRequired<MachineBlockHashInfo>();
 }
 
 bool AsmPrinter::doInitialization(Module &M) {
@@ -1427,7 +1432,8 @@ getBBAddrMapFeature(const MachineFunction &MF, int NumMBBSectionRanges,
           BrProbEnabled,
           MF.hasBBSections() && NumMBBSectionRanges > 1,
           static_cast<bool>(BBAddrMapSkipEmitBBEntries),
-          HasCalls};
+          HasCalls,
+          static_cast<bool>(EmitBBHash)};
 }
 
 void AsmPrinter::emitBBAddrMapSection(const MachineFunction &MF) {
@@ -1486,6 +1492,8 @@ void AsmPrinter::emitBBAddrMapSection(const MachineFunction &MF) {
       PrevMBBEndSymbol = MBBSymbol;
     }
 
+    auto MBHI = Features.BBHash ? &getAnalysis<MachineBlockHashInfo>() : nullptr;
+
     if (!Features.OmitBBEntries) {
       OutStreamer->AddComment("BB id");
       // Emit the BB ID for this basic block.
@@ -1513,6 +1521,10 @@ void AsmPrinter::emitBBAddrMapSection(const MachineFunction &MF) {
       emitLabelDifferenceAsULEB128(MBB.getEndSymbol(), CurrentLabel);
       // Emit the Metadata.
       OutStreamer->emitULEB128IntValue(getBBAddrMapMetadata(MBB));
+      // Emit the Hash.
+      if (MBHI) {
+        OutStreamer->emitULEB128IntValue(MBHI->getMBBHash(MBB));
+      }
     }
     PrevMBBEndSymbol = MBB.getEndSymbol();
   }
diff --git a/llvm/lib/CodeGen/BasicBlockMatchingAndInference.cpp b/llvm/lib/CodeGen/BasicBlockMatchingAndInference.cpp
new file mode 100644
index 0000000000000..aacfaf88d03c0
--- /dev/null
+++ b/llvm/lib/CodeGen/BasicBlockMatchingAndInference.cpp
@@ -0,0 +1,172 @@
+#include "llvm/CodeGen/BasicBlockMatchingAndInference.h"
+#include "llvm/CodeGen/BasicBlockSectionsProfileReader.h"
+#include "llvm/CodeGen/MachineBlockHashInfo.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/InitializePasses.h"
+#include <llvm/Support/CommandLine.h>
+
+using namespace llvm;
+
+static cl::opt<float>
+    PropellerInferThreshold("propeller-infer-threshold",
+                            cl::desc("Threshold for infer stale profile"),
+                            cl::init(0.6), cl::Optional);
+
+/// The object is used to identify and match basic blocks given their hashes.
+class StaleMatcher {
+public:
+  /// Initialize stale matcher.
+  void init(const std::vector<MachineBasicBlock *> &Blocks,
+            const std::vector<BlendedBlockHash> &Hashes) {
+    assert(Blocks.size() == Hashes.size() &&
+           "incorrect matcher initialization");
+    for (size_t I = 0; I < Blocks.size(); I++) {
+      MachineBasicBlock *Block = Blocks[I];
+      uint16_t OpHash = Hashes[I].OpcodeHash;
+      OpHashToBlocks[OpHash].push_back(std::make_pair(Hashes[I], Block));
+    }
+  }
+
+  /// Find the most similar block for a given hash.
+  MachineBasicBlock *matchBlock(BlendedBlockHash BlendedHash) const {
+    auto BlockIt = OpHashToBlocks.find(BlendedHash.OpcodeHash);
+    if (BlockIt == OpHashToBlocks.end()) {
+      return nullptr;
+    }
+    MachineBasicBlock *BestBlock = nullptr;
+    uint64_t BestDist = std::numeric_limits<uint64_t>::max();
+    for (auto It : BlockIt->second) {
+      MachineBasicBlock *Block = It.second;
+      BlendedBlockHash Hash = It.first;
+      uint64_t Dist = Hash.distance(BlendedHash);
+      if (BestBlock == nullptr || Dist < BestDist) {
+        BestDist = Dist;
+        BestBlock = Block;
+      }
+    }
+    return BestBlock;
+  }
+
+private:
+  using HashBlockPairType = std::pair<BlendedBlockHash, MachineBasicBlock *>;
+  std::unordered_map<uint16_t, std::vector<HashBlockPairType>> OpHashToBlocks;
+};
+
+INITIALIZE_PASS_BEGIN(BasicBlockMatchingAndInference,
+                      "machine-block-match-infer",
+                      "Machine Block Matching and Inference Analysis", true,
+                      true)
+INITIALIZE_PASS_DEPENDENCY(MachineBlockHashInfo)
+INITIALIZE_PASS_DEPENDENCY(BasicBlockSectionsProfileReaderWrapperPass)
+INITIALIZE_PASS_END(BasicBlockMatchingAndInference, "machine-block-match-infer",
+                    "Machine Block Matching and Inference Analysis", true, true)
+
+char BasicBlockMatchingAndInference::ID = 0;
+
+BasicBlockMatchingAndInference::BasicBlockMatchingAndInference()
+    : MachineFunctionPass(ID) {
+  initializeBasicBlockMatchingAndInferencePass(
+      *PassRegistry::getPassRegistry());
+}
+
+void BasicBlockMatchingAndInference::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.addRequired<MachineBlockHashInfo>();
+  AU.addRequired<BasicBlockSectionsProfileReaderWrapperPass>();
+  AU.setPreservesAll();
+  MachineFunctionPass::getAnalysisUsage(AU);
+}
+
+std::optional<BasicBlockMatchingAndInference::WeightInfo>
+BasicBlockMatchingAndInference::getWeightInfo(StringRef FuncName) const {
+  auto It = ProgramWeightInfo.find(FuncName);
+  if (It == ProgramWeightInfo.end()) {
+    return std::nullopt;
+  }
+  return It->second;
+}
+
+BasicBlockMatchingAndInference::WeightInfo
+BasicBlockMatchingAndInference::initWeightInfoByMatching(MachineFunction &MF) {
+  std::vector<MachineBasicBlock *> Blocks;
+  std::vector<BlendedBlockHash> Hashes;
+  auto BSPR = &getAnalysis<BasicBlockSectionsProfileReaderWrapperPass>();
+  auto MBHI = &getAnalysis<MachineBlockHashInfo>();
+  for (auto &Block : MF) {
+    Blocks.push_back(&Block);
+    Hashes.push_back(BlendedBlockHash(MBHI->getMBBHash(Block)));
+  }
+  StaleMatcher Matcher;
+  Matcher.init(Blocks, Hashes);
+  BasicBlockMatchingAndInference::WeightInfo MatchWeight;
+  auto [Flag, PathAndClusterInfo] =
+      BSPR->getFunctionPathAndClusterInfo(MF.getName());
+  if (!Flag)
+    return std::move(MatchWeight);
+  for (auto &BlockCount : PathAndClusterInfo.NodeCounts) {
+    if (PathAndClusterInfo.BBHashes.count(BlockCount.first.BaseID)) {
+      auto Hash = PathAndClusterInfo.BBHashes[BlockCount.first.BaseID];
+      MachineBasicBlock *Block = Matcher.matchBlock(BlendedBlockHash(Hash));
+      // When a basic block has clone copies, sum their counts.
+      if (Block != nullptr)
+        MatchWeight.BlockWeights[Block] += BlockCount.second;
+    }
+  }
+  for (auto &PredItem : PathAndClusterInfo.EdgeCounts) {
+    auto PredID = PredItem.first.BaseID;
+    if (!PathAndClusterInfo.BBHashes.count(PredID))
+      continue;
+    auto PredHash = PathAndClusterInfo.BBHashes[PredID];
+    MachineBasicBlock *PredBlock = Matcher.matchBlock(BlendedBlockHash(PredHash));
+    if (PredBlock == nullptr)
+      continue;
+    for (auto &SuccItem : PredItem.second) {
+      auto SuccID = SuccItem.first.BaseID;
+      auto EdgeWeight = SuccItem.second;
+      if (PathAndClusterInfo.BBHashes.count(SuccID)) {
+        auto SuccHash = PathAndClusterInfo.BBHashes[SuccID];
+        MachineBasicBlock *SuccBlock = Matcher.matchBlock(BlendedBlockHash(SuccHash));
+        // When an edge has clone copies, sum their counts.
+        if (SuccBlock != nullptr)
+          MatchWeight.EdgeWeights[std::make_pair(PredBlock, SuccBlock)] += EdgeWeight;
+      }
+    }
+  }
+  return std::move(MatchWeight);
+}
+
+void BasicBlockMatchingAndInference::generateWeightInfoByInference(
+    MachineFunction &MF,
+    BasicBlockMatchingAndInference::WeightInfo &MatchWeight) {
+  BlockEdgeMap Successors;
+  for (auto &Block : MF) {
+    for (auto *Succ : Block.successors())
+      Successors[&Block].push_back(Succ);
+  }
+  SampleProfileInference<MachineFunction> SPI(
+      MF, Successors, MatchWeight.BlockWeights, MatchWeight.EdgeWeights);
+  BlockWeightMap BlockWeights;
+  EdgeWeightMap EdgeWeights;
+  SPI.apply(BlockWeights, EdgeWeights);
+  ProgramWeightInfo.try_emplace(
+      MF.getName(), BasicBlockMatchingAndInference::WeightInfo{
+                        std::move(BlockWeights), std::move(EdgeWeights)});
+}
+
+bool BasicBlockMatchingAndInference::runOnMachineFunction(MachineFunction &MF) {
+  if (MF.empty())
+    return false;
+  auto MatchWeight = initWeightInfoByMatching(MF);
+  // If the ratio of the number of MBBs in matching to the total number of MBBs
+  // in the function is less than the threshold value, the processing should be
+  // abandoned.
+  if (static_cast<float>(MatchWeight.BlockWeights.size()) / MF.size() <
+      PropellerInferThreshold) {
+    return false;
+  }
+  generateWeightInfoByInference(MF, MatchWeight);
+  return false;
+}
+
+MachineFunctionPass *llvm::createBasicBlockMatchingAndInferencePass() {
+  return new BasicBlockMatchingAndInference();
+}
diff --git a/llvm/lib/CodeGen/BasicBlockSections.cpp b/llvm/lib/CodeGen/BasicBlockSections.cpp
index e317e1c06741f..3e9791b8f60f4 100644
--- a/llvm/lib/CodeGen/BasicBlockSections.cpp
+++ b/llvm/lib/CodeGen/BasicBlockSections.cpp
@@ -72,6 +72,7 @@
 #include "llvm/ADT/StringRef.h"
 #include "llvm/CodeGen/BasicBlockSectionUtils.h"
 #include "llvm/CodeGen/BasicBlockSectionsProfileReader.h"
+#include "llvm/CodeGen/BasicBlockMatchingAndInference.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
@@ -81,6 +82,7 @@
 #include "llvm/InitializePasses.h"
 #include "llvm/Support/UniqueBBID.h"
 #include "llvm/Target/TargetMachine.h"
+#include "llvm/Transforms/Utils/CodeLayout.h"
 #include <optional>
 
 using namespace llvm;
@@ -175,6 +177,77 @@ updateBranches(MachineFunction &MF,
   }
 }
 
+// This function generates the machine basic block clusters of "hot" blocks.
+// Currently, only support one cluster creation.
+// TODO: Support multi-cluster creation and path cloning.
+static std::pair<bool, SmallVector<BBClusterInfo>> 
+createBBClusterInfoForFunction(
+    const MachineFunction &MF, 
+    BasicBlockMatchingAndInference *BMI) {
+  unsigned CurrentCluster = 0;
+  auto OptWeightInfo = BMI->getWeightInfo(MF.getName());
+  if (!OptWeightInfo)
+    return std::pair(false, SmallVector<BBClusterInfo>{});
+  auto BlockWeights = OptWeightInfo->BlockWeights;
+  auto EdgeWeights = OptWeightInfo->EdgeWeights;
+
+  SmallVector<const MachineBasicBlock *, 4> HotMBBs;
+  if (MF.size() <= 2) {
+    for (auto &MBB : MF) {
+      if (MBB.isEntryBlock() || BlockWeights[&MBB] > 0) {
+        HotMBBs.push_back(&MBB);
+      }
+    }
+  } else {
+    SmallVector<uint64_t, 0> BlockSizes(MF.size());
+    SmallVector<uint64_t, 0> BlockCounts(MF.size());
+    std::vector<const MachineBasicBlock *> OrigOrder;
+    OrigOrder.reserve(MF.size());
+    SmallVector<codelayout::EdgeCount, 0> JumpCounts;
+
+    // Init the MBB size and count.
+    for (auto &MBB : MF) {
+      auto NonDbgInsts =
+          instructionsWithoutDebug(MBB.instr_begin(), MBB.instr_end());
+      int NumInsts = std::distance(NonDbgInsts.begin(), NonDbgInsts.end());
+      BlockSizes[MBB.getNumber()] = 4 * NumInsts;
+      BlockCounts[MBB.getNumber()] = BlockWeights[&MBB];
+      OrigOrder.push_back(&MBB);
+    }
+
+    // Init the edge count.
+    for (auto &MBB : MF) {
+      for (auto *Succ : MBB.successors()) {
+        auto EdgeWeight = EdgeWeights[std::make_pair(&MBB, Succ)];
+        JumpCounts.push_back({static_cast<uint64_t>(MBB.getNumber()),
+                              static_cast<uint64_t>(Succ->getNumber()),
+                              EdgeWeight});
+      }
+    }
+
+    // Run the layout algorithm.
+    auto Result = computeExtTspLayout(BlockSizes, BlockCounts, JumpCounts);
+    for (uint64_t R : Result) {
+      auto Block = OrigOrder[R];
+      if (Block->isEntryBlock() || BlockWeights[Block] > 0)
+        HotMBBs.push_back(Block);
+    }
+  }
+  
+  // Generate the "hot" basic block cluster.
+  if(!HotMBBs.empty()) {
+    SmallVector<BBClusterInfo, 4> BBClusterInfos;
+    unsigned CurrentPosition = 0;
+    for (auto &MBB : HotMBBs) {
+      if (MBB->getBBID()) {
+        BBClusterInfos.push_back({*(MBB->getBBID()), CurrentCluster, CurrentPosition++});
+      }
+    }
+    return std::pair(true, std::move(BBClusterInfos));
+  }
+  return std::pair(false, SmallVector<BBClusterInfo>{});
+}
+
 // This function sorts basic blocks according to the cluster's information.
 // All explicitly specified clusters of basic blocks will be ordered
 // accordingly. All non-specified BBs go into a separate "Cold" section.
@@ -314,12 +387,17 @@ bool BasicBlockSections::handleBBSections(MachineFunction &MF) {
 
   DenseMap<UniqueBBID, BBClusterInfo> FuncClusterInfo;
   if (BBSectionsType == BasicBlockSection::List) {
-    auto [HasProfile, ClusterInfo] =
+    std::pair<bool, SmallVector<BBClusterInfo>> ExpClusterInfo;
+    if (auto *BMI = getAnalysisIfAvailable<BasicBlockMatchingAndInference>()) {
+      ExpClusterInfo = createBBClusterInfoForFunction(MF, BMI);
+    } else {
+      ExpClusterInfo = 
         getAnalysis<BasicBlockSectionsProfileReaderWrapperPass>()
             .getClusterInfoForFunction(MF.getName());
-    if (!HasProfile)
+    }
+    if (!ExpClusterInfo.first)
       return false;
-    for (auto &BBClusterInfo : ClusterInfo) {
+    for (auto &BBClusterInfo : ExpClusterInfo.second) {
       FuncClusterInfo.try_emplace(BBClusterInfo.BBID, BBClusterInfo);
     }
   }
@@ -402,6 +480,7 @@ bool BasicBlockSections::runOnMachineFunction(MachineFunction &MF) {
 void BasicBlockSections::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.setPreservesAll();
   AU.addRequired<BasicBlockSectionsProfileReaderWrapperPass>();
+  AU.addUsedIfAvailable<BasicBlockMatchingAndInference>();
   AU.addUsedIfAvailable<MachineDominatorTreeWrapperPass>();
   AU.addUsedIfAvailable<MachinePostDominatorTreeWrapperPass>();
   MachineFunctionPass::getAnalysisUsage(AU);
diff --git a/llvm/lib/CodeGen/BasicBlockSectionsProfileReader.cpp b/llvm/lib/CodeGen/BasicBlockSectionsProfileReader.cpp
index fbcd614b85d18..00e13135bb064 100644
--- a/llvm/lib/CodeGen/BasicBlockSectionsProfileReader.cpp
+++ b/llvm/lib/CodeGen/BasicBlockSectionsProfileReader.cpp
@@ -91,6 +91,15 @@ uint64_t BasicBlockSectionsProfileReader::getEdgeCount(
   return EdgeIt->second;
 }
 
+std::pair<bool, FunctionPathAndClusterInfo>
+BasicBlockSectionsProfileReader::getFunctionPathAndClusterInfo(
+    StringRef FuncName) const {
+  auto R = ProgramPathAndClusterInfo.find(getAliasName(FuncName));
+  return R != ProgramPathAndClusterInfo.end()
+             ? std::pair(true, R->second)
+             : std::pair(false, FunctionPathAndClusterInfo());
+}
+
 // Reads the version 1 basic block sections profile. Profile for each function
 // is encoded as follows:
 //   m <module_name>
@@ -287,6 +296,24 @@ Error BasicBlockSectionsProfileReader::ReadV1Profile() {
       }
       continue;
     }
+    case 'h': { // Basic block hash secifier.
+      // Skip the profile when we the profile iterator (FI) refers to the
+      // past-the-end element.
+      if (FI == ProgramPathAndClusterInfo.end())
+        continue;
+      for (auto BBIDHashStr : Values) {
+        auto [BBIDStr, HashStr] = BBIDHashStr.split(':');
+        unsigned long long BBID = 0, Hash = 0;
+        if (getAsUnsignedInteger(BBIDStr, 10, BBID))
+          return createProfileParseError(
+              Twine("unsigned integer expected: '") + BBIDStr + "'");
+        if (getAsUnsignedInteger(HashStr, 10, Hash))
+          return createProfileParseError(
+              Twine("unsigned integer expected: '") + HashStr + "'");
+        FI->second.BBHashes[BBID] = Hash;
+      }
+      continue;
+    }
     default:
       return createProfileParseError(Twine("invalid specifier: '") +
                                      Twine(Specifier) + "'");
@@ -493,6 +520,12 @@ uint64_t BasicBlockSectionsProfileReaderWrapperPass::getEdgeCount(
   return BBSPR.getEdgeCount(FuncName, SrcBBID, SinkBBID);
 }
 
+std::pair<bool, FunctionPathAndClusterInfo>
+BasicBlockSectionsProfileReaderWrapperPass::getFunctionPathAndClusterInfo(
+    StringRef FuncName) const {
+  return BBSPR.getFunctionPathAndClusterInfo(FuncName);
+}
+
 BasicBlockSectionsProfileReader &
 BasicBlockSectionsProfileReaderWrapperPass::getBBSPR() {
   return BBSPR;
diff --git a/llvm/lib/CodeGen/CMakeLists.txt b/llvm/lib/CodeGen/CMakeLists.txt
index f8f9bbba53e43..ee66c7b549048 100644
--- a/llvm/lib/CodeGen/CMakeLists.txt
+++ b/llvm/lib/CodeGen/CMakeLists.txt
@@ -35,6 +35,7 @@ add_llvm_component_library(LLVMCodeGen
   BasicBlockSections.cpp
   BasicBlockPathCloning.cpp
   BasicBlockSectionsProfileReader.cpp
+  BasicBlockMatchingAndInference.cpp
   CalcSpillWeights.cpp
   CallBrPrepare.cpp
   CallingConvLower.cpp
@@ -108,6 +109,7 @@ add_llvm_component_library(LLVMCodeGen
   LowerEmuTLS.cpp
   MachineBasicBlock.cpp
   MachineBlockFrequencyInfo.cpp
+  MachineBlockHashInfo.cpp
   MachineBlockPlacement.cpp
   MachineBranchProbabilityInfo.cpp
   MachineCFGPrinter.cpp
diff --git a/llvm/lib/CodeGen/MachineBlockHashInfo.cpp b/llvm/lib/CodeGen/MachineBlockHashInfo.cpp
new file mode 100644
index 0000000000000..a9636bd09a1a2
--- /dev/null
+++ b/llvm/lib/CodeGen/MachineBlockHashInfo.cpp
@@ -0,0 +1,111 @@
+#include "llvm/CodeGen/MachineBlockHashInfo.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Target/TargetMachine.h"
+
+using namespace llvm;
+
+using OperandHashFuncTy =
+    function_ref<uint64_t(uint64_t &, const MachineOperand &)>;
+
+uint64_t hashBlock(const MachineBasicBlock &MBB,
+                   OperandHashFuncTy OperandHashFunc) {
+  uint64_t Hash = 0;
+  for (const MachineInstr &MI : MBB) {
+    if (MI.isMetaInstruction())
+      continue;
+    // Ignore terminator instruction
+    if (MI.isTerminator())
+      continue;
+    Hash = hashing::detail::hash_16_bytes(Hash, MI.getOpcode());
+    for (unsigned i = 0; i < MI.getNumOperands(); i++) {
+      Hash = OperandHashFunc(Hash, MI.getOperand(i));
+    }
+  }
+  return Hash;
+}
+
+/// Hashing a 64-bit integer to a 16-bit one.
+uint16_t hash_64_to_16(const uint64_t Hash) {
+  uint16_t Res = (uint16_t)(Hash & 0xFFFF);
+  Res ^= (uint16_t)((Hash >> 16) & 0xFFFF);
+  Res ^= (uint16_t)((Hash >> 32) & 0xFFFF);
+  Res ^= (uint16_t)((Hash >> 48) & 0xFFFF);
+  return Res;
+}
+
+uint64_t hashInstOperand(uint64_t &Hash, const MachineOperand &Operand) {
+  return hashing::detail::hash_16_bytes(Hash, hash_value(Operand));
+}
+
+INITIALIZE_PASS(MachineBlockHashInfo, "machine-block-hash",
+                "Machine Block Hash Analysis", true, true)
+
+char MachineBlockHashInfo::ID = 0;
+
+MachineBlockHashInfo::MachineBlockHashInfo() : MachineFunctionPass(ID) {
+  initializeMachineBlockHashInfoPass(*PassRegistry::getPassRegistry());
+}
+
+void MachineBlockHashInfo::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+  MachineFunctionPass::getAnalysisUsage(AU);
+}
+
+bool MachineBlockHashInfo::runOnMachineFunction(MachineFunction &F) {
+  DenseMap<MachineBasicBlock *, BlendedBlockHash> BlendedHashes;
+  DenseMap<MachineBasicBlock *, uint64_t> OpcodeHashes;
+  uint16_t Offset = 0;
+  // Initialize hash components
+  for (MachineBasicBlock &MBB : F) {
+    BlendedBlockHash BlendedHash;
+    // offset of the machine basic block
+    BlendedHash.Offset = Offset;
+    Offset += MBB.size();
+    // Hashing opcodes
+    uint64_t OpcodeHash = hashBlock(
+        MBB, [](uint64_t &Hash, const MachineOperand &Op) { return Hash; });
+    OpcodeHashes[&MBB] = OpcodeHash;
+    BlendedHash.OpcodeHash = hash_64_to_16(OpcodeHash);
+    // Hash complete instructions
+    uint64_t InstrHash = hashBlock(MBB, hashInstOperand);
+    BlendedHash.InstrHash = hash_64_to_16(InstrHash);
+    BlendedHashes[&MBB] = BlendedHash;
+  }
+
+  // Initialize neighbor hash
+  for (MachineBasicBlock &MBB : F) {
+    uint64_t Hash = OpcodeHashes[&MBB];
+    // Append hashes of successors
+    for (MachineBasicBlock *SuccMBB : MBB.successors()) {
+      uint64_t SuccHash = OpcodeHashes[SuccMBB];
+      Hash = hashing::detail::hash_16_bytes(Hash, SuccHash);
+    }
+    // Append hashes of predecessors
+    for (MachineBasicBlock *PredMBB : MBB.predecessors()) {
+      uint64_t PredHash = OpcodeHashes[PredMBB];
+      Hash = hashing::detail::hash_16_bytes(Hash, PredHash);
+    }
+    BlendedHashes[&MBB].NeighborHash = hash_64_to_16(Hash);
+  }
+
+  // Assign hashes
+  for (MachineBasicBlock &MBB : F) {
+    if (MBB.getBBID()) {
+      MBBHashInfo[MBB.getBBID()->BaseID] = BlendedHashes[&MBB].combine();
+    }
+  }
+
+  return false;
+}
+
+uint64_t MachineBlockHashInfo::getMBBHash(const MachineBasicBlock &MBB) {
+  if (MBB.getBBID()) {
+    return MBBHashInfo[MBB.getBBID()->BaseID];
+  }
+  return 0;
+}
+
+MachineFunctionPass *llvm::createMachineBlockHashInfoPass() {
+  return new MachineBlockHashInfo();
+}
diff --git a/llvm/lib/CodeGen/TargetPassConfig.cpp b/llvm/lib/CodeGen/TargetPassConfig.cpp
index b6169e6c4dc34..11022d6d9d915 100644
--- a/llvm/lib/CodeGen/TargetPassConfig.cpp
+++ b/llvm/lib/CodeGen/TargetPassConfig.cpp
@@ -272,6 +272,16 @@ static cl::opt<bool>
                     cl::desc("Split static data sections into hot and cold "
                              "sections using profile information"));
 
+/// Enable matching and inference when using propeller.
+static cl::opt<bool>
+    PropellerMatchInfer("propeller-match-infer", 
+                        cl::desc("Use match&infer to evaluate stale profile"),
+                        cl::init(false), cl::Optional);
+
+cl::opt<bool> EmitBBHash("emit-bb-hash", 
+    cl::desc("Emit the hash of basic block in the SHT_LLVM_BB_ADDR_MAP section."), 
+    cl::init(false), cl::Optional);
+
 /// Allow standard passes to be disabled by command line options. This supports
 /// simple binary flags that either suppress the pass or do nothing.
 /// i.e. -disable-mypass=false has no effect.
@@ -1281,10 +1291,15 @@ void TargetPassConfig::addMachinePasses() {
   // address map (or both).
   if (TM->getBBSectionsType() != llvm::BasicBlockSection::None ||
       TM->Options.BBAddrMap) {
+    if (EmitBBHash || PropellerMatchInfer)
+      addPass(llvm::createMachineBlockHashInfoPass());
     if (TM->getBBSectionsType() == llvm::BasicBlockSection::List) {
       addPass(llvm::createBasicBlockSectionsProfileReaderWrapperPass(
           TM->getBBSectionsFuncListBuf()));
-      addPass(llvm::createBasicBlockPathCloningPass());
+      if (PropellerMatchInfer)
+        addPass(llvm::createBasicBlockMatchingAndInferencePass());
+      else
+        addPass(llvm::createBasicBlockPathCloningPass());
     }
     addPass(llvm::createBasicBlockSectionsPass());
   }
diff --git a/llvm/lib/Object/ELF.cpp b/llvm/lib/Object/ELF.cpp
index 53699ce0d4fcf..e0b51483413a4 100644
--- a/llvm/lib/Object/ELF.cpp
+++ b/llvm/lib/Object/ELF.cpp
@@ -907,6 +907,7 @@ decodeBBAddrMapImpl(const ELFFile<ELFT> &EF,
           uint32_t Size = readULEB128As<uint32_t>(Data, Cur, ULEBSizeErr) +
                           LastCallsiteEndOffset;
           uint32_t MD = readULEB128As<uint32_t>(Data, Cur, ULEBSizeErr);
+          uint64_t Hash = FeatEnable.BBHash ? readULEB128As<uint64_t>(Data, Cur, ULEBSizeErr) : 0;
           Expected<BBAddrMap::BBEntry::Metadata> MetadataOrErr =
               BBAddrMap::BBEntry::Metadata::decode(MD);
           if (!MetadataOrErr) {
@@ -914,7 +915,7 @@ decodeBBAddrMapImpl(const ELFFile<ELFT> &EF,
             break;
           }
           BBEntries.push_back({ID, Offset + PrevBBEndOffset, Size,
-                               *MetadataOrErr, CallsiteEndOffsets});
+                               *MetadataOrErr, CallsiteEndOffsets, Hash});
           PrevBBEndOffset += Offset + Size;
         }
         TotalNumBlocks += BBEntries.size();
diff --git a/llvm/lib/ObjectYAML/ELFEmitter.cpp b/llvm/lib/ObjectYAML/ELFEmitter.cpp
index faeeab32f5ad2..4a2eb684af776 100644
--- a/llvm/lib/ObjectYAML/ELFEmitter.cpp
+++ b/llvm/lib/ObjectYAML/ELFEmitter.cpp
@@ -1526,6 +1526,9 @@ void ELFState<ELFT>::writeSectionContent(
         }
         SHeader.sh_size += CBA.writeULEB128(BBE.Size);
         SHeader.sh_size += CBA.writeULEB128(BBE.Metadata);
+        if (FeatureOrErr->BBHash && BBE.Hash) {
+          SHeader.sh_size += CBA.writeULEB128(*BBE.Hash);
+        }
       }
     }
     if (!PGOAnalyses)
diff --git a/llvm/lib/ObjectYAML/ELFYAML.cpp b/llvm/lib/ObjectYAML/ELFYAML.cpp
index d9cce1eb7641d..421d6603c08c3 100644
--- a/llvm/lib/ObjectYAML/ELFYAML.cpp
+++ b/llvm/lib/ObjectYAML/ELFYAML.cpp
@@ -1887,6 +1887,7 @@ void MappingTraits<ELFYAML::BBAddrMapEntry::BBEntry>::mapping(
   IO.mapRequired("Size", E.Size);
   IO.mapRequired("Metadata", E.Metadata);
   IO.mapOptional("CallsiteEndOffsets", E.CallsiteEndOffsets);
+  IO.mapOptional("Hash", E.Hash);
 }
 
 void MappingTraits<ELFYAML::PGOAnalysisMapEntry>::mapping(
diff --git a/llvm/test/CodeGen/X86/basic-block-address-map-with-bb-hash.ll b/llvm/test/CodeGen/X86/basic-block-address-map-with-bb-hash.ll
new file mode 100644
index 0000000000000..466d0e0181d27
--- /dev/null
+++ b/llvm/test/CodeGen/X86/basic-block-address-map-with-bb-hash.ll
@@ -0,0 +1,96 @@
+; Check the basic block sections labels option when emit basic block hash.
+; RUN: llc < %s -mtriple=x86_64 -function-sections -unique-section-names=true -basic-block-address-map -emit-bb-hash | FileCheck %s --check-prefixes=CHECK,UNIQ
+; RUN: llc < %s -mtriple=x86_64 -function-sections -unique-section-names=false -basic-block-address-map -emit-bb-hash | FileCheck %s --check-prefixes=CHECK,NOUNIQ
+; RUN: llc < %s -mtriple=x86_64 -function-sections -unique-section-names=true -basic-block-address-map -split-machine-functions -emit-bb-hash | FileCheck %s --check-prefixes=CHECK,UNIQ
+
+define void @_Z3bazb(i1 zeroext, i1 zeroext) personality ptr @__gxx_personality_v0 {
+  br i1 %0, label %3, label %8
+
+3:
+  %4 = invoke i32 @_Z3barv()
+          to label %8 unwind label %6
+  br label %10
+
+6:
+  landingpad { ptr, i32 }
+          catch ptr null
+  br label %12
+
+8:
+  %9 = call i32 @_Z3foov()
+  br i1 %1, label %12, label %10
+
+10:
+  %11 = select i1 %1, ptr blockaddress(@_Z3bazb, %3), ptr blockaddress(@_Z3bazb, %12) ; <ptr> [#uses=1]
+  indirectbr ptr %11, [label %3, label %12]
+
+12:
+  ret void
+}
+
+declare i32 @_Z3barv() #1
+
+declare i32 @_Z3foov() #1
+
+declare i32 @__gxx_personality_v0(...)
+
+; UNIQ:			.section .text._Z3bazb,"ax", at progbits{{$}}
+; NOUNIQ:		.section .text,"ax", at progbits,unique,1
+; CHECK-LABEL:	_Z3bazb:
+; CHECK-LABEL:	.Lfunc_begin0:
+; CHECK-LABEL:	.LBB_END0_0:
+; CHECK-LABEL:	.LBB0_1:
+; CHECK-LABEL:  .LBB0_1_CS0:
+; CHECK-LABEL:	.LBB_END0_1:
+; CHECK-LABEL:	.LBB0_2:
+; CHECK-LABEL:  .LBB0_2_CS0:
+; CHECK-LABEL:	.LBB_END0_2:
+; CHECK-LABEL:	.LBB0_3:
+; CHECK-LABEL:	.LBB_END0_3:
+; CHECK-LABEL:	.Lfunc_end0:
+
+; UNIQ:			.section	.llvm_bb_addr_map,"o", at llvm_bb_addr_map,.text._Z3bazb{{$}}
+;; Verify that with -unique-section-names=false, the unique id of the text section gets assigned to the llvm_bb_addr_map section.
+; NOUNIQ:		.section	.llvm_bb_addr_map,"o", at llvm_bb_addr_map,.text,unique,1
+; CHECK-NEXT:   .byte   3		# version
+; CHECK-NEXT:   .byte   96		# feature
+; CHECK-NEXT:	.quad	.Lfunc_begin0	# function address
+; CHECK-NEXT:	.byte	6		# number of basic blocks
+; CHECK-NEXT:   .byte	0		# BB id
+; CHECK-NEXT:	.uleb128 .Lfunc_begin0-.Lfunc_begin0
+; CHECK-NEXT:   .byte	0		# number of callsites
+; CHECK-NEXT:	.uleb128 .LBB_END0_0-.Lfunc_begin0
+; CHECK-NEXT:	.byte	8
+; CHECK-NEXT:   .ascii "{{.*}}"
+; CHECK-NEXT:   .byte	1		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_1-.LBB_END0_0
+; CHECK-NEXT:   .byte	1		# number of callsites
+; CHECK-NEXT:	.uleb128 .LBB0_1_CS0-.LBB0_1
+; CHECK-NEXT:	.uleb128 .LBB_END0_1-.LBB0_1_CS0
+; CHECK-NEXT:	.byte	8
+; CHECK-NEXT:   .ascii "{{.*}}"
+; CHECK-NEXT:   .byte	3		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_2-.LBB_END0_1
+; CHECK-NEXT:   .byte	1		# number of callsites
+; CHECK-NEXT:	.uleb128 .LBB0_2_CS0-.LBB0_2
+; CHECK-NEXT:	.uleb128 .LBB_END0_2-.LBB0_2_CS0
+; CHECK-NEXT:	.byte	8
+; CHECK-NEXT:   .ascii "{{.*}}"
+; CHECK-NEXT:   .byte	4		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_3-.LBB_END0_2
+; CHECK-NEXT:   .byte	0		# number of callsites
+; CHECK-NEXT:	.uleb128 .LBB_END0_3-.LBB0_3
+; CHECK-NEXT:	.byte	16
+; CHECK-NEXT:   .ascii "{{.*}}"
+; CHECK-NEXT:   .byte	5		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_4-.LBB_END0_3
+; CHECK-NEXT:   .byte	0		# number of callsites
+; CHECK-NEXT:	.uleb128 .LBB_END0_4-.LBB0_4
+; CHECK-NEXT:	.byte	1
+; CHECK-NEXT:   .ascii "{{.*}}"
+; CHECK-NEXT:   .byte	2		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_5-.LBB_END0_4
+; CHECK-NEXT:   .byte	0		# number of callsites
+; CHECK-NEXT:	.uleb128 .LBB_END0_5-.LBB0_5
+; CHECK-NEXT:	.byte	5
+; CHECK-NEXT:   .ascii "{{.*}}"
diff --git a/llvm/test/tools/obj2yaml/ELF/bb-addr-map-pgo-analysis-map.yaml b/llvm/test/tools/obj2yaml/ELF/bb-addr-map-pgo-analysis-map.yaml
index 299bf463cf4bc..01e987a8c1b05 100644
--- a/llvm/test/tools/obj2yaml/ELF/bb-addr-map-pgo-analysis-map.yaml
+++ b/llvm/test/tools/obj2yaml/ELF/bb-addr-map-pgo-analysis-map.yaml
@@ -228,5 +228,4 @@ Sections:
 # MISSING-FEC-NEXT:      Sections:
 # MISSING-FEC-NEXT:        - Name:    .llvm_bb_addr_map
 # MISSING-FEC-NEXT:          Type:    SHT_LLVM_BB_ADDR_MAP
-# MISSING-FEC-NEXT:          Content: '{{([[:xdigit:]]+)}}'{{$}}
-
+MISSING-FEC-NEXT:          Content: '{{([[:xdigit:]]+)}}'{{$}}
diff --git a/llvm/unittests/Object/ELFObjectFileTest.cpp b/llvm/unittests/Object/ELFObjectFileTest.cpp
index 17d9f5076b73f..615ce110f2113 100644
--- a/llvm/unittests/Object/ELFObjectFileTest.cpp
+++ b/llvm/unittests/Object/ELFObjectFileTest.cpp
@@ -988,6 +988,126 @@ TEST(ELFObjectFileTest, InvalidDecodePGOAnalysisMap) {
   }
 }
 
+// Test for the ELFObjectFile::readBBAddrMap API with BBHash.
+TEST(ELFObjectFileTest, ReadBBHash) {
+  StringRef CommonYamlString(R"(
+--- !ELF
+FileHeader:
+  Class: ELFCLASS64
+  Data:  ELFDATA2LSB
+  Type:  ET_EXEC
+Sections:
+  - Name: .llvm_bb_addr_map_1
+    Type: SHT_LLVM_BB_ADDR_MAP
+    Link: 1
+    Entries:
+      - Version: 3
+        Feature: 0x60
+        BBRanges:
+          - BaseAddress: 0x11111
+            BBEntries:
+              - ID:              1
+                AddressOffset:   0x0
+                Size:            0x1
+                Metadata:        0x2
+                CallsiteEndOffsets: [ 0x1 , 0x1 ]
+                Hash:            0x1
+  - Name: .llvm_bb_addr_map_2
+    Type: SHT_LLVM_BB_ADDR_MAP
+    Link: 1
+    Entries:
+      - Version: 3
+        Feature: 0x48
+        BBRanges:
+          - BaseAddress: 0x22222
+            BBEntries:
+              - ID:            2
+                AddressOffset: 0x0
+                Size:          0x2
+                Metadata:      0x4
+                Hash:          0x2
+          - BaseAddress: 0xFFFFF
+            BBEntries:
+              - ID:            15
+                AddressOffset: 0xF0
+                Size:          0xF1
+                Metadata:      0x1F
+                Hash:          0xF
+  - Name: .llvm_bb_addr_map_3
+    Type: SHT_LLVM_BB_ADDR_MAP
+    Link: 2
+    Entries:
+      - Version: 3
+        Feature: 0x40
+        BBRanges:
+          - BaseAddress: 0x33333
+            BBEntries:
+              - ID:            0
+                AddressOffset: 0x0
+                Size:          0x3
+                Metadata:      0x6
+                Hash:          0x3
+  - Name: .llvm_bb_addr_map_4
+    Type: SHT_LLVM_BB_ADDR_MAP
+  # Link: 0 (by default, can be overriden)
+    Entries:
+      - Version: 3
+        Feature: 0x40
+        BBRanges:
+          - BaseAddress: 0x44444
+            BBEntries:
+              - ID:            0
+                AddressOffset: 0x0
+                Size:          0x4
+                Metadata:      0x18
+                Hash:          0x4
+)");
+
+  BBAddrMap E1 = {
+      {{0x11111,
+        {{1, 0x0, 0x3, {false, true, false, false, false}, {0x1, 0x2}, 0x1}}}}};
+  BBAddrMap E2 = {
+      {{0x22222, {{2, 0x0, 0x2, {false, false, true, false, false}, {}, 0x2}}},
+       {0xFFFFF, {{15, 0xF0, 0xF1, {true, true, true, true, true}, {}, 0xF}}}}};
+  BBAddrMap E3 = {
+      {{0x33333, {{0, 0x0, 0x3, {false, true, true, false, false}, {}, 0x3}}}}};
+  BBAddrMap E4 = {
+      {{0x44444, {{0, 0x0, 0x4, {false, false, false, true, true}, {}, 0x4}}}}};
+
+  std::vector<BBAddrMap> Section0BBAddrMaps = {E4};
+  std::vector<BBAddrMap> Section1BBAddrMaps = {E3};
+  std::vector<BBAddrMap> Section2BBAddrMaps = {E1, E2};
+  std::vector<BBAddrMap> AllBBAddrMaps = {E1, E2, E3, E4};
+
+  auto DoCheckSucceeds = [&](StringRef YamlString,
+                             std::optional<unsigned> TextSectionIndex,
+                             std::vector<BBAddrMap> ExpectedResult) {
+    SCOPED_TRACE("for TextSectionIndex: " +
+                 (TextSectionIndex ? llvm::Twine(*TextSectionIndex) : "{}") +
+                 " and object yaml:\n" + YamlString);
+    SmallString<0> Storage;
+    Expected<ELFObjectFile<ELF64LE>> ElfOrErr =
+        toBinary<ELF64LE>(Storage, YamlString);
+    ASSERT_THAT_EXPECTED(ElfOrErr, Succeeded());
+
+    Expected<const typename ELF64LE::Shdr *> BBAddrMapSecOrErr =
+        ElfOrErr->getELFFile().getSection(1);
+    ASSERT_THAT_EXPECTED(BBAddrMapSecOrErr, Succeeded());
+    auto BBAddrMaps = ElfOrErr->readBBAddrMap(TextSectionIndex);
+    ASSERT_THAT_EXPECTED(BBAddrMaps, Succeeded());
+    EXPECT_EQ(*BBAddrMaps, ExpectedResult);
+  };
+
+  DoCheckSucceeds(CommonYamlString, /*TextSectionIndex=*/std::nullopt,
+                  AllBBAddrMaps);
+  DoCheckSucceeds(CommonYamlString, /*TextSectionIndex=*/0,
+                  Section0BBAddrMaps);
+  DoCheckSucceeds(CommonYamlString, /*TextSectionIndex=*/2,
+                  Section1BBAddrMaps);
+  DoCheckSucceeds(CommonYamlString, /*TextSectionIndex=*/1,
+                  Section2BBAddrMaps);
+}
+
 // Test for the ELFObjectFile::readBBAddrMap API with PGOAnalysisMap.
 TEST(ELFObjectFileTest, ReadPGOAnalysisMap) {
   StringRef CommonYamlString(R"(
diff --git a/llvm/unittests/Object/ELFTypesTest.cpp b/llvm/unittests/Object/ELFTypesTest.cpp
index f88931b5f544c..5a77f403ecb9f 100644
--- a/llvm/unittests/Object/ELFTypesTest.cpp
+++ b/llvm/unittests/Object/ELFTypesTest.cpp
@@ -128,9 +128,9 @@ TEST(ELFTypesTest, BBAddrMapFeaturesEncodingTest) {
 
 TEST(ELFTypesTest, BBAddrMapFeaturesInvalidEncodingTest) {
   const std::array<std::string, 2> Errors = {
-      "invalid encoding for BBAddrMap::Features: 0x40",
+      "invalid encoding for BBAddrMap::Features: 0x80",
       "invalid encoding for BBAddrMap::Features: 0xf0"};
-  const std::array<uint8_t, 2> Values = {{0b100'0000, 0b1111'0000}};
+  const std::array<uint8_t, 2> Values = {{0b1000'0000, 0b1111'0000}};
   for (const auto &[Val, Error] : llvm::zip(Values, Errors)) {
     EXPECT_THAT_ERROR(BBAddrMap::Features::decode(Val).takeError(),
                       FailedWithMessage(Error));



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